This invention pertains generally to air cart units, also referred to as air seeders, and more specifically to controlling air flow settings for seeding units consisting of one or multiple storage hoppers.
Agricultural practices are becoming more demanding as the requirements for increased yield and better quality crop output are growing. Satisfying these demands is important for a farm operation to remain competitive. One measure that aids in meeting these demands is providing equipment that allows for accurate seed placement during planting in a quick and efficient manner. The design of planting units is continuously being changed in an attempt to improve their performance.
Planting units have long since been equipped with methods of improving the accuracy and control by which seeds are placed in furrows. Planting units commonly use air flow to transport seed from a storage hopper to the seed boot and into the ground. Such prior art are disclosed in U.S. Pat No. 4,296,695 issued to Quanbeck, U.S. Pat. No. 4,473,016 issued to Gust, U.S. Pat. No. 4,503,786 issued to Tautfest and U.S. Pat. No. 5,161,473 Landphair.
Pneumatic systems are also used to transport materials through tubes in applications not limited to agriculture. An arrangement for a machine is disclosed in U.S. Pat. No. 4,634,522 issued to Edholm. In this invention, particles are entrained in an air flow and carried through the system for the purpose of separating larger particles from smaller particles. The invention also discloses a throttling device as means to control the air flow.
In the prior art of pneumatic air carts, a number of disadvantages exist. Earlier designs consisted of several moving parts. This resulted in equipment that was complex and difficult to maintain. Also, these designs were costly to manufacture and operate. Another drawback of prior art is the lack of adaptability in controlling the air flow and seed delivery rate. Correct air flow settings and fan speed are important to ensure proper placement of seeds in furrows. Utilizing the minimum amount of air reduces seed bounce and reduces seed damage that can occur from high velocity impact. Adequate air flow settings also ensure that air distribution lines remain free of debris which can obstruct the seed flow and ensure that they do not become clogged during seed transport from the metering boxes to the seed boot. Using only the minimum required air flow settings also uses minimal power, lowering the overall power required to operate the distribution system. Another benefit of correct air flow settings is that when the air system is shut down, the primary run hoses will quickly and evenly empty out.
U.S. Pat. No. 5,161,473 discloses a pneumatic air seeder that controls the seed delivery rate by adjusting the angle of and size of the seed delivery tube. This adjustment of the seed tube is difficult and cumbersome to perform.
Ensuring correct air flow settings has been a common problem in air carts with multiple tanks. When different products are traveling in separate air flow tubes or runs, the amount of air necessary to move each product is different. The 4000 series air seeder manufactured by Bourgault is designed to accommodate up to triple shoot applications. In this case, the air seeder is equipped with two fans. The design is such that one fan controls the air flow settings in one run and the second fan controls the air flow settings for the remaining two runs. Knife valves are used to open or close off runs. The airflow is predominately controlled by the fan settings of individual runs.
The majority of air seeders are equipped with a single fan used to generate the air flow. In these cases, when double or triple shoot applications are employed, controlling the air flow in each individual set of runs has proven to be a problem.
Case IH introduced their 2300 air system that was designed to handle double shoot applications. The air volume in each run is controlled by baffles that are situated in either side of the blower on the air seeder. Each baffle is positioned by a bolt. The operator can adjust the baffle position to control whether more or less air travels in the run by either tightening or loosening each bolt. This system, while allowing for varying air flow volume settings, does not have any means to indicate the baffle position, and thus no means to indicate the resulting air flow settings. The process becomes a guessing game of how much or little to adjust each bolt.
Other air seeder designs also incorporate damping mechanisms of various natures to control the amount of air carried through each tube. New Noble utilizes a damping mechanism on their 92 series air seeders, Harmon uses an air damper as standard equipment on all air seeders and European manufacturer Rabe Werk also has incorporated a damping lever on their air seeders.
The 7000 series air seeder manufactured by Morris is designed to accommodate double shoot applications. When the air seeder is configured for double shoot, a plenum damper is used to control the air flow settings in each run. Each plenum damper can be set to the fully open, three quarters, one half, one quarter or fully closed position. An indicator panel is situated by each damper to inform the operator where to position the damper for any of these settings. Again, the damping mechanism is manually adjusted by the operator.
The John Deere 1900 air seeder uses a damper mechanism to control the air flow volume for single and double shoot applications. The damper is hand positioned by use of a crank. The position of the damper is determined by a color coded position indicator rod. This method is acceptable for single shoot applications (when the damper is positioned to completely shut off one run) or in double shoot applications when equal amounts of air flow are necessary (and the damper is positioned in the center). But, even in these cases when the damper is fairly easy to position, the process is again cumbersome and inefficient.
In double shoot applications, it is uncommon that both products will require equal amounts of air. Quite often, the required air flows are different for each product. Using the John Deere 1900 air seeder damper design, the operator will have difficulty determining how to position the hand crank in order to achieve the desired air flow volumes for each run. This necessitates trial and error to determine the damper position that results in the correct air flows.
Currently, the damping mechanism designed by these farm equipment manufacturers are all fully manual. The position of the damper is controlled by a hand crank or lever. If the air flow needs to be adjusted during planting, the operator is required to cease planting and adjust the hand crank. This results in inefficient use of precious seeding time.
The 50 series air seeder manufactured by Flexi-Coil is a three tank air seeder. It is designed such that each of the three runs has an air damper located at each metering box in the primary lines. The dampers are also positioned using a lever that is manually positioned by the operator. The lever is situated on the body of the cart. This method has proven to be time consuming and cumbersome. Also, adjusting the air flow has proven to be difficult since the air flow in each tube is dependent upon one another. Adjusting the air dampers to achieve the optimum air velocity and volume depending upon the products being planted has been a tedious process of trial and error. Also, controlling and changing the fan RPM has been difficult to do. None of the above operations can be performed `on the go`. The operator has to cease planting and manually change the required airflow settings.
All these drawbacks of the prior art can lead to unnecessary complexity. In light of the growing size of farm equipment, including planting units which consist of three or more storage tanks, a great deal of time and money can be lost simply on the maintenance of such seed distribution designs. Improved maintenance would result in ease of operation, time saving benefits and cost saving benefits.
It would be desirable then, to provide a means of remote monitoring and controlling of fan speed and air damper settings to achieve optimum particle velocity in the air distribution lines of an air cart. It would also be desirable to provide an improved system that allows for fan speed and air damper setting adjustments while the planting unit is in operation.